1. Field of the Invention
The invention relates to emulsifiers for the preparation of polysiloxane oil emulsions and polysiloxane-paraffin oil emulsions.
2. Discussion of the Background
Siloxane oils are used in a great many applications, for example as release agents, slip agents, foam inhibitors, water repellents, carriers for skin restoratives, in plastics processing, in the glass and ceramics industries, in textile production and also in detergent, cosmetic and dermatological formulations. In these applications, the preferred form of the siloxane oils are as water-thinnable oil-in-water emulsions. The preparation of these emulsions is known to be difficult (cf. Ullmanns Enzyklopadie der technischen Chemie, 3rd Ed., Vol. 15, p. 783) and usually requires water-soluble or oil-soluble agents such as alcohols or amines as disclosed in DE-A-1,033,894, and high concentrations of emulsifiers and/or high shear forces, optionally combined with a gel-like final state. A gel provides a certain stability to the emulsion due to high viscosity, as taught in DE-A-3,024,870. Other processes for the preparation of siloxane oil-in-water emulsions are limited to relatively low molecular weight siloxanes (DE-A-3,045,083) or can only be carried out at elevated temperature under vigorous evolution of gas (DE-A-2,730,923). Obviously in the latter case, chemical changes to the polysiloxane accompany the emulsification.